   "Return the most specific concept of the interpretation of dl-exp in
   model."
   [model dl-exp]
-  (most-specific-concept model (interpret model dl-exp)))
+  (with-memoized-fns [interpret]        ;?
+    (most-specific-concept model (interpret model dl-exp))))
 
 ;;;
 

                                                   (model-interpretation model))))]
    (.write out (.trim output))))

;;; Interpretation

(defmulti compile-expression
  "Compiles an expression to a function mapping a model to the extent

     (fn [~model]
       ~@body)))

;;; Model Syntax

(defmacro model
  "Defines model for language on base-set: interpretation maps atomic
